Exhaust valve guides Mitsubishi 4G63

Applicable Mitsubishi engines

This set fits the exhaust side of the 2-litre Mitsubishi 4G63 four-cylinder, turbo (4G63T) or naturally aspirated, found under the bonnet of Lancer Evolution, Eclipse, Galant VR-4 and Outlander Turbo models.

Eight of the engine's sixteen valves are exhaust valves, each turning in a guide pressed into the head. FERREA gives a 6.55 mm stem on the exhaust side, SUPERTECH a guide for a 6.6 mm stem; the sizes below are those of the makers.

FERREA and SUPERTECH exhaust valve guides

On the exhaust side the valve stem takes the heat of the burnt gas. The guide holds it on the seat axis, sends part of that heat back into the head and receives the stem seal. Once worn, it lets the valve close crooked and oil pass into the port: blue smoke, oil vanishing faster, compression that weakens. Because the exhaust valve is not cooled by the fresh charge, the guide is one of its main paths for shedding heat.

The FERREA catalogue presents a copper bronze of American origin, heat-treated by a process of the brand: heat better removed, good temperature stability, wear held back, stem lubricated. Precise CNC machining suits titanium as well as stainless valves. SUPERTECH picks a manganese bronze whose heat conduction, according to the brand, clearly exceeds that of the sintered guides fitted as standard. The set gathers the eight exhaust guides of the engine. They are usually paired with reinforced valves.

Valve guide technical specifications

Valve guide installation

Technical guide

Our brands

	FERREA was born in Fort Lauderdale in 1978. Between Florida and Argentina, its plants turn out valves, valve guides, springs and stem seals designed for racing and track use.
	SUPERTECH has developed competition guides, valves, springs and titanium retainers in the Silicon Valley for over thirty years, studied by finite elements.

Standard or oversize?

Two sizes at each brand: standard, or 0.025 mm (0.001") oversize. For SUPERTECH the outside diameter rises from 12.08 to 12.1 mm.

Manganese bronze

An alloy of copper mixed with manganese, a little aluminium, iron and zinc, this bronze is hard and holds up against corrosion as well as repeated rubbing. Heavily loaded bushes are made from it, which naturally suits the guide, where the stem rubs without a break.

When valve guides must be replaced

• Blue smoke from the exhaust stems
• Reinforced valves to fit in a worn cylinder head
• Race head to be redone completely from scratch
• Complete overhaul of the valve train

Vehicle compatibility

Important: these guides are given for the turbo 4G63 and for the Eclipse one, both double overhead cam. Other 4G63 engines are excluded.

Remember the inlet guides and valve stem seals

Add new stem seals too: for the exhaust side, the FERREA catalogue provides the VS1010.